Shares in Foxtons lept as much as 13 per cent this morning after it emerged that David Cameron would be staying on at number 10.

It was thought that Labour’s mansion tax would prompt an exodus of wealthy buyers out of pricey properties in the most expensive parts of central London, to residential areas such as Battersea and Fulham.

Labour had planned a £3,000-a-year levy for homes worth between £2 million and £3 million and the Lib-Dems £2,000 for homes worth between £2 million and £2.5 million.

Savills said the Conservative vcitory means prices in the London suburbs would rise more than those in a central location.

“Prime London markets were looking much more fully priced than those in and beyond the commuter zone, and will have to operate in a relatively high tax environment given stamp duty increases imposed in December 2014,” said Lucian Cook, Savills UK head of residential research.